1. Technical Field
The system of the present disclosure relates generally to the removal of heat from an aircraft gearbox. More particularly, the system relates to the use of a helium gas for heat removal from heat generating frictional areas within the gearbox.
2. Description of Related Art
Aircraft drivetrains can include various components that produce and transfer power. For example, engines and gearboxes are common components. Such components generate heat and require lubrication. Excessive levels of heat can cause premature failure and create safety risks. Proper lubrication serves to reduce heat production and assist in heat removal from within moving components.
Typically, aircraft use a variety of primary lubrication systems to provide wear protection and heat transfer within components. Under normal operating conditions, primary lubrication systems provide proper lubrication and heat removal. However, in cases of emergency, primary lubrication systems can fail resulting in excessive wear and failure of components, such as a gearbox or transmission.
Aircraft are generally required to maintain manageable flight operations for selected durations of time if the primary lubrication system fails (zero pressure). One method used to satisfy the requirements of manageable flight during a lubrication system failure is to increase the amount of lubricant reserves with resulting increase in the weight of the lubricant. Another method is to use a secondary lubrication system to operate when the primary lubrication system fails. Although not commonly used, secondary systems typically provide only sufficient lubricant to lubricate moving parts but can fail to adequately remove heat. Both methods increase the overall weight of the aircraft and can fail to remove adequate amounts of heat. An improved method of controlling heat transfer from an aircraft gearbox is desired.
Although great strides have been made in managing heat transfer in a gearbox, considerable shortcomings remain.